Question

(2y+3)(2y-3)-(1+2y)2 при y=0,5

Answer 1

$(2 \times 0.5+ 3)(2 \times 0.5 - 3) - (1 + 2 \times 0.5) \times 2 \\ (1 + 3)(1 - 3) - (1 + 1) \times 2 \\ 4( - 2) - 2 \times 2 \\ - 4 \times 2 - 2 \times 2 \\ - 2(2 \times 2 + 2) \\ - 2(4 + 2) \\ - 2 \times 6 \\ - 12$